Hello,
Shorter length. W12 can fit in same space as V8 motor. Audi A8, Bentley Continental GT, and VW Phaeton have W12 motor ahead of of front axle.
Same for W8 fitting in same space as V6 motor in Passat. We might not see W8 again in next generation of Passat due to its lacklustre sales.
Oliver
House of Ch> What's the advantages (if any) of a W-12 engine over a V-12 engine ?